HomePod mini won't play sound from Mac Safari via AirPlay after Sonoma update

Reddit user u/joaobborges found a fix: disconnect ethernet cable and use wifi. Worked for me. Link to their post:

(1) HomePod not playing via airplay on Sonoma : MacOS (reddit.com)

Same issue but it doesn't matter what source I use. Browser (chrome, safari, edge), iTunes, appletv--no sound from Mac mini over HomePod after Sonoma update. HomePods light up as if they're working, but no sound. Still works fine from iPad/iPhone.

Not true, has nothing to do with Ethernet. Same Problem in an all Wifi based setting.  The music time bar of Mac OS Music app progresses as normal but there is no sound anymore. This happened even before Sonoma from time to time, now it's happening with almost every song.

Similar issue. Mac Mini connected to an Airport Express to play music. It worked fine yesterday in Ventura before upgrading to Sonoma last night. Now I can't get any audio to play via Airplay. I can connect to a Bluetooth speaker directly, but no Airplay.

• I have restarted the Base Station, as well as the Airport Express (twice). Also restarted the computer.

• I found a command line on a Reddit discussion: 'sudo killall coreaudiod' No difference.

The only temporary solution I have found is to disable the ethernet in system prefs and unplug the ethernet cord. This allows me to connect via Airplay to the Airport Express.

I tried re-enabling ethernet at this point, and the music still works until the computer goes to sleep. When it wakes from up, I once again can't connect to Airplay without going through the disable ethernet process again.

It does for me: I can unplug ethernet cable at either the router or the back of a Mac Studio where the sound quits after a couple seconds; replug and have the sound pickup again. Contextually nothing else is happening—it is the ethernet connection.